A stage circuit included in a gate driver of a display device, includes: a first transistor connected between an input terminal receiving an input signal and a control terminal, and including a gate electrode connected to a first clock terminal receiving a first clock signal: a second transistor connected between a line supplying a gate high voltage and an output terminal generating an output signal, and including a gate electrode connected to an inversion control terminal; a third transistor connected between the output terminal and a second clock terminal receiving a second clock signal, and including a gate electrode connected to the control terminal; a first capacitor connected between the control terminal and the output terminal; and a control circuit configured to controlling an inversion control voltage of the inversion control terminal based on a control voltage of the control terminal.
Legal claims defining the scope of protection, as filed with the USPTO.
a first transistor connected between an input terminal receiving an input signal and a control terminal, the first transistor including a gate electrode connected to a first clock terminal receiving a first clock signal: a second transistor connected between a line supplying a gate high voltage and an output terminal generating an output signal, the second transistor including a gate electrode connected to an inversion control terminal; a third transistor connected between the output terminal and a second clock terminal receiving a second clock signal, the third transistor including a gate electrode connected to the control terminal; a first capacitor connected between the control terminal and the output terminal; and a control circuit configured to control an inversion control voltage of the inversion control terminal based on a control voltage of the control terminal, wherein, in a first operation period, the first clock signal and the input signal are at a logic low level, the second clock signal is at a logic high level, and the control voltage is at the logic low level, wherein, in a second operation period after the first operation period, the first clock signal, the second clock signal and the input signal are at the logic high level, and the control voltage maintains the logic low level, wherein, in a third operation period after the second operation period, the second clock signal is at the logic low level, the first clock signal and the input signal are at the logic high level, and the control voltage is boosted to a boosting level lower than the logic low level, wherein, in a fourth operation period after the third operation period, the first clock signal, the second clock signal and the input signal are at the logic high level, and the control voltage is restored to the logic low level from the boosting level, and wherein, in a fifth operation period after the fourth operation period, the first clock signal is at the logic low level, the input signal and the second clock signal are at the logic high level, and the control voltage is at the logic high level. . A stage circuit included in a gate driver of a display device, comprising:
180 claim 1 wherein a horizontal time allocated to drive one row of the display device is ½ of the clock cycle. . The stage circuit of, wherein the first clock signal and the second clock signal have a same clock cycle, have a phase difference ofdegrees from each other, and are each at a logic low level for ¼ of the clock cycle, and,
claim 1 . The stage circuit of, wherein the first transistor, the second transistor, and the third transistor are P-type metal oxide semiconductor (PMOS) transistors.
claim 1 . The stage circuit of, wherein the output signal is at the logic low level in the third operation period, and the output signal is at the logic high level in the first operation period, the second operation period, the fourth operation period and the fifth operation period.
claim 1 . The stage circuit of, wherein the inversion control voltage is at the logic low level in the fifth operation period, and the inversion control voltage is at the logic high level in the first operation period, the second operation period, the third operation period and the fourth operation period.
claim 1 a fourth transistor connected between the line supplying the gate high voltage and the inversion control terminal, the fourth transistor including a gate electrode connected to the control terminal; and a second capacitor connected between the first clock terminal and the inversion control terminal. . The stage circuit of, wherein the control circuit includes:
claim 6 . The stage circuit of, wherein the first transistor, the second transistor, the third transistor and the fourth transistor are PMOS transistors.
claim 1 a fourth transistor connected between the line supplying the gate high voltage and the inversion control terminal, the fourth transistor including a gate electrode connected to the second clock terminal; an enhancement transistor connected between a line supplying a gate low voltage and the inversion control terminal, the enhancement transistor including a gate electrode connected to the control terminal; and a second capacitor connected between the line supplying the gate high voltage and the inversion control terminal. . The stage circuit of, wherein the control circuit includes:
claim 8 . The stage circuit of, wherein the first transistor, the second transistor, the third transistor and the fourth transistor are PMOS transistors, and the enhancement transistor is an NMOS transistor.
claim 1 a fourth transistor connected between the first clock terminal and the inversion control terminal, the fourth transistor including a gate electrode connected to the control terminal; and an enhancement transistor connected between a line supplying a gate low volta and the inversion control terminal, the enhancement transistor including a gate electrod connected to the control terminal. . The stage circuit of, wherein the control circuit includes:
claim 10 . The stage circuit of, wherein the first transistor, the second transistor, the third transistor and the fourth transistor are PMOS transistors, and the enhancement transistor is an NMOS transistor.
claim 1 a load-reduction transistor connected in series with the first transistor between the input terminal and the control terminal, the load-reduction transistor including a gat electrode receiving a gate low voltage. . The stage circuit of, further comprising:
claim 1 . The stage circuit of, wherein the control circuit includes one transistor and one capacitor.
claim 1 . The stage circuit of, wherein the control circuit includes two transistors.
a first transistor connected between an input terminal receiving an input signal and a control terminal, the first transistor including a gate electrode connected to a first clock terminal receiving a first clock signal: a second transistor connected between a line supplying a gate high voltage and an output terminal generating an output signal, the second transistor including a gate electrode connected to an inversion control terminal; a third transistor connected between the output terminal and a second clock terminal receiving a second clock signal, the third transistor including a gate electrode connected to the control terminal; a first capacitor connected between the control terminal and the output terminal; and a control circuit configured to control an inversion control voltage of the inversion control terminal based on a control voltage of the control terminal, wherein the control circuit includes: a fourth transistor connected between the line supplying the gate high voltage and the inversion control terminal, the fourth transistor including a gate electrode connected to the control terminal; an enhancement transistor connected between a line supplying a gate low voltage and the inversion control terminal, the enhancement transistor including a gate electrode connected to the control terminal; and a second capacitor connected between the line supplying the gate high voltage and the inversion control terminal. . A stage circuit included in a gate driver of a display device, comprising:
claim 15 . The stage circuit of, wherein the first transistor, the second transistor, the third transistor and the fourth transistor are PMOS transistors, and the enhancement transistor is an N-type metal oxide semiconductor (NMOS) transistor.
a display panel including a pixel; a gate driver configured to output a gate signal to the pixel; a data driver configured to output a data voltage to the pixel; and an emission driver configured to output an emission signal to the pixel, wherein the gate driver includes at least one stage circuit, and a first transistor connected between an input terminal receiving an input signal and a control terminal, the first transistor including a gate electrode connected to a first clock terminal receiving a first clock signal: a second transistor connected between a line supplying a gate high voltage and an output terminal generating an output signal, the second transistor including a gate electrode connected to an inversion control terminal; a third transistor connected between the output terminal and a second clock terminal receiving a second clock signal, the third transistor including a gate electrode connected to the control terminal; a first capacitor connected between the control terminal and the output terminal; and a control circuit configured to control an inversion control voltage of the inversion control terminal based on a control voltage of the control terminal, wherein the stage circuit includes: wherein, in a first operation period, the first clock signal and the input signal are at a logic low level, the second clock signal is at a logic high level, and the control voltage is at the logic low level, wherein, in a second operation period after the first operation period, the first clock signal, the second clock signal and the input signal are at the logic high level, and the control voltage maintains the logic low level, wherein, in a third operation period after the second operation period, the second clock signal is at the logic low level, the first clock signal and the input signal are at the logic high level, and the control voltage is boosted to a boosting level lower than the logic low level, wherein, in a fourth operation period after the third operation period, the first clock signal, the second clock signal and the input signal are at the logic high level, and the control voltage is restored to the logic low level from the boosting level, and wherein, in a fifth operation period after the fourth operation period, the first clock signal is at the logic low level, the input signal and the second clock signal are at the logic high level, and the control voltage is at the logic high level. . A display device comprising
Complete technical specification and implementation details from the patent document.
This application claims priority to Korean Patent Application No. 10-2024-0029677, filed on Feb. 29, 2024, and all the benefits accruing therefrom under 35 U.S.C. § 119, the content of which in its entirety is herein incorporated by reference.
Example embodiments relate generally to diving of a display device, and more particularly to a stage circuit of a gate driver and a display device including the stage circuit.
A display device includes a display panel and a display panel driver. The display panel may include a plurality of gate lines, a plurality of data lines, a plurality of emission lines and a plurality of pixels. The display panel driver includes a gate driver providing gate signals to the gate lines, a data driver providing data voltages to the data lines, an emission driver providing emission signals to the emission lines, and a drive controller controlling the gate driver, the data driver and the emission driver. The drivers (e.g., the gate driver and/or the emission driver) of the display device may provide signals (e.g., gate signals and/or emission signals) to the pixels of the display panel in a row-by-row sequence. To provide the signals sequentially on a row-by-row basis, the driver may be implemented in the form of a shift register including a plurality of stage circuits.
In general, each stage circuit of the driver may include primarily only a single type of transistor, for example, a p-type metal oxide semiconductor (“PMOS”) transistor. When each stage circuit includes only the PMOS transistors, in order to output an output signal with a low voltage level, a bootstrapping operation is performed to reduce the voltage of the internal nodes of the stage circuit to a voltage level lower than the low voltage level of the output signal. The display device includes a large number of stage circuits, and there is a problem that the dead space of the display panel increases significantly as the size of each stage circuit increases.
Some example embodiments may provide a stage circuit of a gate driver having a reduced size.
Some example embodiments may provide a display device having a reduced dead space, using the stage circuits.
According to example embodiments, a stage circuit included in a gate driver of a display device, includes: a first transistor, a second transistor, a third transistor, a first capacitor and a control circuit. The first transistor is connected between an input terminal receiving an input signal and a control terminal, and the first transistor includes a gate electrode connected to a first clock terminal receiving a first clock signal. The second transistor is connected between a line supplying a gate high voltage and an output terminal generating an output signal, and the second transistor includes a gate electrode connected to an inversion control terminal. The third transistor is connected between the output terminal and a second clock terminal receiving a second clock signal, and the third transistor includes a gate electrode connected to the control terminal. The first capacitor is connected between the control terminal and the output terminal. The control circuit controls an inversion control voltage of the inversion control terminal based on a control voltage of the control terminal.
In some example embodiments, the first clock signal and the second clock signal may have the same clock cycle, have a phase difference of 180 degrees from each other, and are at a logic low level for ¼ of the clock cycle. A horizontal time allocated to drive one row of the display device may be ½ of the clock cycle.
In some example embodiments, the first transistor, the second transistor, and the third transistor may be P-type metal oxide semiconductor (PMOS) transistors.
In some example embodiments, in a first operation period, the first clock signal and the input signal may be at a logic low level, the second clock signal is at a logic high level, and the control voltage may be at the logic low level. In a second operation period after the first operation period, the first clock signal, the second clock signal and the input signal may be at the logic high level, and the control voltage may maintain the logic low level. In a third operation period after the second operation period, the second clock signal may be at the logic low level, the first clock signal and the input signal may be at the logic high level, and the control voltage may be boosted to a boosting level lower than the logic low level. In a fourth operation period after the third operation period, the first clock signal, the second clock signal and the input signal may be at the logic high level, and the control voltage may be restored to the logic low level from the boosting level. In a fifth operation period after the fourth operation period, the first clock signal may be at the logic low level, the input signal and the second clock signal may be at the logic high level, and the control voltage may be at the logic high level.
In some example embodiments, the output signal may be at the logic low level in the third operation period, and the output signal may be at the logic high level in the first operation period, the second operation period, the fourth operation period and the fifth operation period.
In some example embodiments, the inversion control voltage may be at the logic low level in the fifth operation period, and the inversion control voltage may be at the logic high level in the first operation period, the second operation period, the third operation period and the fourth operation period.
In some example embodiments, the control circuit may include a fourth transistor and a second capacitor. The fourth transistor may be connected between the line supplying the gate high voltage and the inversion control terminal, and the fourth transistor may include a gate electrode connected to the control terminal. The second capacitor may be connected between the first clock terminal and the inversion control terminal.
In some example embodiments, the first transistor, the second transistor, the third transistor and the fourth transistor may be PMOS transistors.
In some example embodiments, the control circuit may include a fourth transistor, an enhancement transistor and a second capacitor. The fourth transistor may be connected between the line supplying the gate high voltage and the inversion control terminal, and the fourth transistor may include a gate electrode connected to the control terminal. The enhancement transistor may be connected between a line supplying a gate low voltage and the inversion control terminal, and the enhancement transistor may include a gate electrode connected to the control terminal. The second capacitor may be connected between the line supplying the gate high voltage and the inversion control terminal. The first transistor, the second transistor, the third transistor and the fourth transistor may be PMOS transistors, and the enhancement transistor may be an N-type metal oxide semiconductor (“NMOS”) transistor.
In some example embodiments, the control circuit may include a fourth transistor, an enhancement transistor and a second capacitor. The fourth transistor may be connected between the line supplying the gate high voltage and the inversion control terminal, and the fourth transistor may include a gate electrode connected to the second clock terminal. The enhancement transistor may be connected between a line supplying a gate low voltage and the inversion control terminal, and the enhancement transistor may include a gate electrode connected to the control terminal. The second capacitor may be connected between the line supplying the gate high voltage and the inversion control terminal. The first transistor, the second transistor, the third transistor and the fourth transistor may be PMOS transistors, and the enhancement transistor may be an NMOS transistor.
In some example embodiments, the control circuit may include a fourth transistor and an enhancement transistor. The fourth transistor may be connected between the first clock terminal and the inversion control terminal, and the fourth transistor may include a gate electrode connected to the control terminal. The enhancement transistor may be connected between a line supplying a gate low voltage and the inversion control terminal, and the enhancement transistor may include a gate electrode connected to the control terminal. The first transistor, the second transistor, the third transistor and the fourth transistor may be PMOS transistors, and the enhancement transistor may be an NMOS transistor.
In some example embodiments, the stage circuit may further include a load-reduction transistor connected in series with the first transistor between the input terminal and the control terminal, and the load-reduction transistor includes a gate electrode receiving a gate low voltage.
In some example embodiments, the control circuit may include one transistor and one capacitor.
In some example embodiments, the control circuit may include two transistors.
According to example embodiments, a stage circuit included in a gate driver of a display device, includes: a first P-type metal oxide semiconductor (PMOS) transistor connected between an input terminal receiving an input signal and a control terminal, the first PMOS transistor including a gate electrode connected to a first clock terminal receiving a first clock signal, a second PMOS transistor connected between a line supplying a gate high voltage and an output terminal generating an output signal, the second PMOS transistor including a gate electrode connected to an inversion control terminal. a third PMOS transistor connected between the output terminal and a second clock terminal receiving a second clock signal, the third PMOS transistor including a gate electrode connected to the control terminal, a fourth PMOS transistor connected between the line supplying the gate high voltage and the inversion control terminal, the fourth PMOS transistor including a gate electrode connected to the control terminal, a first capacitor connected between the control terminal and the output terminal, and a second capacitor connected between the first clock terminal and the inversion control terminal.
According to example embodiments, a display device includes: a display panel including a pixel, a gate driver configured to output a gate signal to the pixel, a data driver configured to output a data voltage to the pixel, and an emission driver configured to output an emission signal to the pixel. The gate driver includes at least one stage circuit. The stage circuit includes a first transistor connected between an input terminal receiving an input signal and a control terminal, the first transistor including a gate electrode connected to a first clock terminal receiving a first clock signal, a second transistor connected between a line supplying a gate high voltage and an output terminal generating an output signal, the second transistor including a gate electrode connected to an inversion control terminal, a third transistor connected between the output terminal and a second clock terminal receiving a second clock signal, the third transistor including a gate electrode connected to the control terminal, a first capacitor connected between the control terminal and the output terminal, and a control circuit configured to control an inversion control voltage of the inversion control terminal based on a control voltage of the control terminal.
The stage circuit according to example embodiments may be implemented with fewer transistors, thereby reducing the size of the gate driver including the stage circuits and reducing the dead space in the display panel without sacrificing performance of the gate driver.
In addition, the stage circuit according to example embodiments may utilize boosting via capacitors to improve the waveform of the output signal, thereby enhancing the performance of the display device including the stage circuits.
Further, the stage circuit according to example embodiments may remove unnecessary operation of the display device and reduce wiring routing in the display device by using fewer transistors and capacitors, thereby improving the design margin of the display device.
The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, “a”, “an,” “the,” and “at least one” do not denote a limitation of quantity, and are intended to include both the singular and plural, unless the context clearly indicates otherwise. For example, “an element” has the same meaning as “at least one element,” unless the context clearly indicates otherwise. “At least one” is not to be construed as limiting “a” or “an.” “Or” means “and/or.” As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises” and/or “comprising,” or “includes” and/or “including” when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof.
It will be understood that, although the terms “first,” “second,” “third” etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or section from another element, component, region, layer or section. Thus, “a first element,” “component,” “region,” “layer” or “section” discussed below could be termed a second element, component, region, layer or section without departing from the teachings herein.
Various example embodiments will be described more fully hereinafter with reference to the accompanying drawings, in which some example embodiments are shown. In the drawings, like numerals refer to like elements throughout. The repeated descriptions may be omitted.
1 FIG. 1 FIG. is a diagram illustrating a stage circuit according to example embodiments. The stage circuit ofmay be included in a gate driver of a display device.
1 FIG. 10 1 2 3 1 20 Referring to, a stage circuitincludes a first transistor T, a second transistor T, a third transistor T, a first capacitor C, and a control circuit (“RCON”).
1 1 1 1 The first transistor Tis connected between an input terminal NI receiving an input signal SIN, and a control terminal Q, and the first transistor Tincludes a gate electrode connected to a first clock terminal NCreceiving a first clock signal CLK.
2 2 The second transistor Tis connected between a line supplying a gate high voltage VGH and an output terminal NO generating an output signal SOUT, and the second transistor Tincludes a gate electrode connected to an inversion control terminal QB.
3 2 2 3 The third transistor Tis connected between the output terminal NO and the second clock terminal NCreceiving a second clock signal CLK, and the third transistor Tincludes a gate electrode connected to a control terminal Q.
1 The first capacitor Cis connected between the control terminal Q and the output terminal NO.
20 20 1 2 8 11 13 15 17 20 FIGS.,,,, and- The control circuitmay control an inversion control voltage VQB of the inversion control terminal QB based on at least a control voltage VQ of the control terminal Q. According to example embodiments, the control circuitmay further receive the gate high voltage VGH, the gate low voltage VGL, the first clock signal CLKand/or the second clock signal CLK(See), in addition to the control voltage VQ, and control the inversion control voltage VQB of the inversion control terminal QB based on the received voltages and signals.
1 FIG. 1 2 3 1 2 3 1 1 In an example embodiment, as shown in, the first transistor T, the second transistor T, and the third transistor Tmay be implemented as P-type metal oxide semiconductor (PMOS) transistors. In this case, the first transistor T, the second transistor T, and the third transistor Tare turned on when the first clock signal CLK, the inversion control voltage VQB, and the control voltage VQ are at a logic low level L or lower level, respectively, and turned off when the first clock signal CLK, the inversion control voltage VQB, and the control voltage VQ are at a logic high level H, respectively.
1 2 3 1 2 3 1 1 In some example embodiments, the first transistor T, the second transistor T, and the third transistor Tmay be implemented as N-type metal oxide semiconductor (NMOS) transistors. In this case, the first transistor T, the second transistor T, and the third transistor Tare turned on when the first clock signal CLK, the inversion control voltage VQB, and the control voltage VQ are at a logic high level H or higher level, respectively, and turned off when the first clock signal CLK, the inversion control voltage VQB, and the control voltage VQ are at a logic low level L, respectively. In some example embodiments, the logic high level H may correspond to the gate high voltage VGH, and the logic low level L may correspond to the gate low voltage VGL.
1 2 3 1 2 3 While example embodiments are described herein with particular reference to cases in which the first transistor T, the second transistor T, and the third transistor Tare implemented with PMOS transistors, those skilled in the art of display devices will understand that example embodiments may also be applicable in which the first transistor T, the second transistor T, and the third transistor Tare implemented with NMOS transistors.
2 FIG. is a timing diagram illustrating an operation of a stage circuit according to example embodiments.
2 FIG. 5 FIG. 1 2 1 2 1 Referring to, the first clock signal CLKand the second clock signal CLKmay have the same clock cycle, and may have a phase difference of 180 degrees from each other. Each of the first clock signal CLKand the second clock signal CLKmay be at the logic low level L for ¼ of the clock cycle. As will be described below with reference to, a horizontal timeH allocated to drive one row of the display device may correspond to ½ of the clock cycle.
10 1 1 2 2 2 3 3 3 4 4 4 5 5 5 6 The operation of the stage circuitmay be described as a first operation period Pbetween time points tand t, a second operation period Pbetween time points tand t, a third operation period Pbetween time points tand t, a fourth operation period Pbetween time points tand t, and a fifth operation period Pbetween time points tand t.
1 2 FIGS.and 1 1 2 Referring to, in the first operation period P, the first clock signal CLKand the input signal SIN may be at the logic low level L and the second clock signal CLKmay be at the logic high level H. At this time, the control voltage VQ may be at the logic low level L and the inversion control voltage VQB may be at the logic high level H.
2 1 1 2 In the second operation period Pafter the first operation period P, the first clock signal CLK, the second clock signal CLKand the input signal SIN may be at the logic high level H. At this time, the control voltage VQ may maintain the logic low level L and the inversion control voltage VQB may maintain the logic high level H.
3 2 2 1 1 In the third operation period Pafter the second operation period P, the second clock signal CLKmay be at the logic low level L, and the first clock signal CLKand the input signal SIN may be at the logic high level H. At this time, the control voltage VQ may be boosted, by coupling of the first capacitor C, to a boosting level L′ lower than the logic low level L.
4 3 1 2 In the fourth operation period Pafter the third operation period P, the first clock signal CLK, the second clock signal CLK, and the input signal SIN may be at the logic high level H. At this time, the control voltage VQ may be restored to the logic low level L from the boosting level L′, and the inversion control voltage VQB may maintain the logic high level H.
5 4 1 2 In the fifth operation period Pafter the fourth operation period P, the first clock signal CLKmay be at the logic low level L and the input signal SIN and the second clock signal CLKmay be at the logic high level H. At this time, the control voltage VQ may be at the logic high level H and the inversion control voltage VQB may be at the logic low level L.
3 1 2 4 5 3 As a result, the output signal SOUT may be at the logic low level L in the third operation period Pand at the logic high level H in the first operation period P, the second operation period P, the fourth operation period P, and the fifth operation period P. The third operation period Pmay be referred to as the output period.
5 1 2 3 4 5 Meanwhile, the reversal control voltage VQB may be at the logic low level L in the fifth operation period Pand at the logic high level H in the first operation period P, the second operation period P, the third operation period P, and the fourth operation period P. The fifth operation period Pmay be referred to as a reset period.
1 1 1 1 Meanwhile, the input signal SIN may be at the logic low level L in the first operation period P, and the first clock signal CLKmay also be at the logic low level L in the first operation period P, such that the activation level of the input signal SIN may be sampled at the control terminal Q. The first operation period Pmay be referred to as a detection period.
10 3 4 5 FIGS.,and Hereinafter, example embodiments of a display device and a gate driver to which the stage circuitis applied according to example embodiments will be described with reference to.
3 FIG. is a block diagram illustrating a display device according to example embodiments.
3 FIG. 100 200 300 400 500 600 Referring to, a display device includes a display paneland a display panel driver. The display panel driver includes a drive controller (“CTRL”), a gate driver (“GDRV”), a gamma reference voltage generator (“GRVG”), a data driver (“DDRV”), and an emission driver (“EDRV”).
100 The display panelincludes a display portion for displaying an image and a peripheral portion disposed adjacent to the display portion.
100 1 2 1 1 The display panelincludes a plurality of gate lines GWL, GCL, GIL and GBL, a plurality of data lines DL, a plurality of emission lines EL, and a plurality of pixels electrically connected to each of the gate lines GWL, GCL, GIL and GBL, the data lines DL, and the emission lines EL. The gate lines GWL, GCL, GIL and GBL extend in a first direction D, the data lines DL extend in a second direction Dintersecting the first direction D, and the emission lines EL extend in the first direction D.
200 The drive controllerreceives input image data IMG and input control signals CONT from an external device. For example, the input image data IMG may include red image data, green image data, and blue image data. According to example embodiments, the input image data IMG may include white image data, magenta image data, yellow image data, and/or cyan image data. The input control signal CONT may include a master clock signal, a data enable signal, and/or a data enable signal. The input control signal CONT may further include a vertical synchronization signal and a horizontal synchronization signal.
200 1 2 3 4 The drive controllergenerates a first control signal CONT, a second control signal CONT, a third control signal CONT, a fourth control signal CONT, and a data signal DATA based on the input image data IMG and the input control signal CONT.
200 1 300 1 300 1 The drive controllergenerates the first control signal CONTfor controlling the operation of the gate driverbased on the input control signal CONT and outputs the first control signal CONTto the gate driver. The first control signal CONTmay include a vertical start signal and a gate clock signal.
200 2 500 2 500 2 The drive controllergenerates the second control signal CONTfor controlling the operation of the data driverbased on the input control signal CONT and outputs the second control signal CONTto the data driver. The second control signal CONTmay include a horizontal start signal and a load signal.
200 500 The drive controllergenerates the data signal DATA based on the input image data IMG, and outputs the data signal DATA to the data driver.
200 3 400 3 400 The drive controllergenerates the third control signal CONTfor controlling the operation of the gamma reference voltage generatorbased on the input control signal CONT, and outputs the third control signal CONTto the gamma reference voltage generator.
200 4 600 4 600 The drive controllergenerates the fourth control signal CONTfor controlling the operation of the emission driverbased on the input control signal CONT, and outputs the fourth control signal CONTto the emission driver.
300 1 200 300 The gate drivergenerates the gate signals for driving the gate lines GWL, GCL, GIL and GBL in response to the first control signal CONTinput from the drive controller. The gate drivermay output the gate signals to the gate lines GWL, GCL, GIL and GBL.
400 3 200 400 500 400 200 500 The gamma reference voltage generatorgenerates a gamma reference voltage VGREF in response to the third control signal CONTinput from the drive controller. The gamma reference voltage generatorprovides the gamma reference voltage VGREF to the data driver. The gamma reference voltage VGREF may have a voltage level corresponding to each data signal DATA. For example, the gamma reference voltage generatormay be disposed within the drive controlleror may be disposed within the data driver.
500 2 200 400 500 500 The data driverreceives the second control signal CONTand the data signal DATA from the drive controller, and receives the gamma reference voltage VGREF from the gamma reference voltage generator. The data driverconverts the data signal DATA into an analog form of the data voltage using the gamma reference voltage VGREF. The data driveroutputs the data voltage to the data line DL.
600 4 200 The emission drivergenerates emission signals to drive the emission lines EL in response to the fourth control signal CONTinput from the drive controller, and outputs the emission signals to the emission lines EL.
3 FIG. 300 100 600 100 300 600 100 300 600 In, for convenience of illustration, the gate driveris shown disposed on a first side of the display paneland the emission driveris shown disposed on a second side of the display panel, but example embodiments are not limited thereto. For example, both the gate driverand the emission drivermay be disposed on the first side of the display panel. For example, the gate driverand the emission drivermay be integrally formed.
4 FIG. 5 FIG. 4 FIG. is a block diagram illustrating an example embodiment of a gate driver included in a display device according to example embodiments, andis a timing diagram illustrating an example operation of the gate driver of.
300 600 The following description will focus on an example embodiment in which a stage circuit according to example embodiments is applied to a gate driver, but the example embodiments are not limited thereto. The stage circuit according to example embodiments may be employed in a gate driver, or may be employed in an emission driver.
4 FIG. 300 1 2 3 4 300 1 2 3 4 1 2 3 4 300 100 300 100 Referring to, the gate drivermay include a plurality of stage circuits STG, STG, STGand STG. The gate drivermay be implemented in the form of a shift register in which the plurality of stage circuits STG, STG, STGand STGsequentially generate output signals OUT, OUT, OUTand OUT. Furthermore, the gate drivermay be formed on the display panelof the display device as a driver included in the display device. For example, the gate drivermay be integrated or formed on a substrate of the display panel.
1 2 3 4 1 2 3 4 1 2 1 2 3 4 2 1 1 3 2 2 4 3 3 The plurality of stage circuits STG, STG, STGand STGmay sequentially generate the output signals OUT, OUT, OUTand OUTas the aforementioned output signals SOUT based on a start signal FLM, the first clock signal CLK, and the second clock signal CLK. Further, the first stage circuit STGmay receive the start signal FLM as the aforementioned input signal SIN, and each of the subsequent stage circuits STG, STGand STGmay receive the output signal of the previous stage circuit as the aforementioned input signal SIN. For example, the second stage circuit STGmay receive the first output signal OUTof the first stage circuit STGas the input signal SIN, the third stage circuit STGmay receive the second output signal OUTof the second stage circuit STGas the input signal SIN, and the fourth stage circuit STGmay receive the third output signal OUTof the third stage circuit STGas the input signal SIN.
1 3 1 3 1 2 4 2 4 2 Further, in an example embodiment, each odd-numbered stage circuit STGand STGmay start outputting the output signals OUTand OUTwhen the first clock signal CLKhas the logic high level, and each even-numbered stage circuit STGand STGmay start outputting the output signal OUTand OUTwhen the second clock signal CLKhas the logic high level.
4 5 FIGS.and 1 1 1 1 1 1 For example, as shown in, when the first clock signal CLKbecomes the logic high level after the start signal FLM becomes the logic high level, the first stage circuit STGmay start outputting the first output signal OUThaving the logic high level. Also, when the first clock signal CLKbecomes the logic high level after the start signal FLM becomes the logic low level, the first stage circuit STGmay begin to output the first output signal OUThaving the logic low level.
1 2 2 2 1 2 2 2 When the first output signal OUTbecomes the logic high level and the second clock signal CLKbecomes the logic high level, the second stage circuit STGmay begin to output the second output signal OUThaving the logic high level. Also, after the first output signal OUTbecomes the logic low level, when the second clock signal CLKbecomes the logic high level, the second stage circuit STGmay begin to output the second output signal OUThaving the logic low level.
2 1 3 3 2 1 3 3 After the second output signal OUTbecomes the logic high level, when the first clock signal CLKbecomes the logic high level, the third stage circuit STGmay begin to output the third output signal OUThaving the logic high level. Also, when the second output signal OUTbecomes the logic low level and the first clock signal CLKbecomes the logic high level, the third stage circuit STGmay begin to output the third output signal OUThaving the logic low level.
3 2 4 4 3 2 4 4 After the third output signal OUTbecomes the logic high level, when the second clock signal CLKbecomes the logic high level, the fourth stage circuit STGmay begin to output the fourth output signal OUThaving the logic high level. Further, when the third output signal OUTbecomes the logic low level and the second clock signal CLKbecomes the logic high level, the fourth stage circuit STGmay begin to output the fourth output signal OUThaving the logic low level.
1 2 3 4 1 2 3 4 1 2 3 4 1 2 1 2 1 In this way, the plurality of stage circuits STG, STG, STGand STGmay sequentially output the output signals OUT, OUT, OUTand OUTwhile delaying or shifting the output signals OUT, OUT, OUTand OUTby ½ of the clock cycle Tc of the first clock signal CLKand the second clock signal CLK. As a result, the first clock signal CLKand the second clock signal CLKmay be at the logic low level L for ¼ of the clock cycle Tc, and may be 180 degrees out of phase with each other. The horizontal timeH allocated to drive one row of the display device may correspond to ½ of the clock cycle Tc.
6 FIG. 7 FIG. 6 FIG. is a circuit diagram illustrating an example embodiment of a pixel included in a display panel according to example embodiments, andis a timing diagram illustrating input signals to the pixel of.
3 7 FIGS.through 100 Referring to, the display panelincludes a plurality of pixels, each of which includes a light emitting element EE.
The pixels receive a write gate signal GW, a compensation gate signal GC, a data initialization gate signal GI, a light emitting element initialization gate signal GB, a data voltage VDATA, and an emission signal EM, and display the image by emitting the light emitting element EE according to the level of the data voltage VDATA.
In this example embodiment, the pixel may include a switching element of a first type and a switching element of a second type that is different from the first type. For example, the first type of switching element may be a P-type transistor, and the second type of switching element may be an N-type transistor.
For example, the first type of switching element may be a polycrystalline silicon thin film transistor. For example, the switching element of the first type may be a low temperature polycrystalline silicon (“LTPS”) thin film transistor. For example, the switching element of the second type may be an oxide thin film transistor.
1 7 At least one of the pixels may include a first to seventh pixel switching element Sto S, a storage capacitor CST, and a light emitting element EE.
1 1 2 3 The first pixel switching element Sincludes a control electrode connected to a first pixel node PN, a first electrode connected to a second pixel node PN, and a second electrode connected to a third pixel node PN.
2 2 The second pixel switching element Sincludes a control electrode to which the write gate signal GW is applied, a first electrode to which the data voltage VDATA is applied, and a second electrode connected to the second pixel node PN.
3 1 3 The third pixel switching element Sincludes a control electrode to which the compensation gate signal GC is applied, a first electrode connected to the first pixel node PN, and a second electrode connected to the third pixel node PN.
4 1 The fourth pixel switching element Sincludes a control electrode to which the data initialization gate signal GI is applied, a first electrode to which an initialization voltage VINT is applied, and a second electrode connected to the first pixel node PN.
5 2 The fifth pixel switching element Sincludes a control electrode to which the emission signal EM is applied, a first electrode to which a high power supply voltage ELVDD is applied, and a second electrode connected to the second pixel node PN.
6 3 The sixth pixel switching element Sincludes a control electrode to which the emission signal EM is applied, a first electrode connected to the third pixel node PN, and a second electrode connected to an anode electrode of the light emission element EE.
7 The seventh pixel switching element Sincludes a control electrode to which the light emitting element initialization gate signal GB is applied, a first electrode to which the initialization voltage VINT is applied, and a second electrode connected to the anode electrode of the light emitting element EE.
1 The storage capacitor CST includes a first electrode to which the high supply voltage ELVDD is applied and a second electrode connected to the first pixel node PN.
The light emitting element EE includes an anode electrode and a cathode electrode to which a low supply voltage ELVSS is applied.
6 FIG. 3 4 1 2 5 6 7 In an example embodiment, as shown in, the third pixel switching element Sand the fourth pixel switching element Smay be N-type transistors, and the first pixel switching element S, the second pixel switching element S, the fifth pixel switching element S, the sixth pixel switching element S, and the seventh pixel switching element Smay be P-type transistors.
7 FIG. 1 1 2 1 1 3 4 100 Referring to, during the first interval DU, the first pixel node PNand the storage capacitor CST are initialized by the data initialization gate signal GI. During the second interval DU, the threshold voltage |VTH| of the first pixel switching element Sis compensated by the write gate signal GW and the compensation gate signal GC, and the data voltage VDATA compensated by the threshold voltage |VTH| is written to the first pixel node PN. During the third interval DU, the anode electrode of the light emitting element EE is initialized by the light emitting element initialization gate signal GB. During the fourth interval DU, the light emitting element EE is emitted by the emission signal EM, and the display paneldisplays the image.
1 2 3 2 1 2 3 In some example embodiments, the off intervals of the emission signal EM are the first, second and third intervals DU, DUand DU, but example embodiments are not limited thereto. The off interval of the emission signal EM may include the data entry interval DU, and the off interval of the emission signal EM may be longer than the first, second and third intervals DU, DUand DU.
1 4 1 In the first segment DU, the data initialization gate signal GI may have an activation level. For example, the activation level of the data initialization gate signal GI may be a high level. When the data initialization gate signal GI has the activation level, the fourth pixel switching element Smay be turned on, such that an initialization voltage VINT may be applied to the first pixel node PN.
2 2 3 1 In the second interval DU, the write gate signal GW and the compensation gate signal GC may have an activation level. For example, the activation level of the write gate signal GW may be a low level, and the activation level of the compensation gate signal GC may be a high level. When the write gate signal GW and the compensation gate signal GC have the above activation levels, the second pixel switching element Sand the third pixel switching element Sare turned on. In addition, the first pixel switching element Sis also turned on by the initialization voltage VINT.
1 2 3 1 1 Along the path formed by the turned-on first to third pixel switching elements S, Sand S, a voltage is set at the first pixel node PNequal to the data voltage VDATA minus the absolute value |VTH| of the threshold voltage of the first pixel switching element S.
3 7 In the third interval DU, the light emitting element initialization gate signal GB may have an activation level. For example, the activation level of the light emitting element initialization gate signal GB may be a logic low level. When the light-emitting element initialization gate signal GB has the above activation level, the seventh pixel switching element Smay be turned on, and an initialization voltage VINT may be applied to the anode electrode of the light emitting element EE.
7 FIG. 4 7 4 7 illustrates a case in which the initialization voltage applied to the fourth pixel switching element Sand the initialization voltage applied to the seventh pixel switching element Sare the same, but example embodiments are not limited thereto. Depending on example embodiment, the initialization voltage applied to the fourth pixel switching element Sand the initialization voltage applied to the seventh pixel switching element Smay be different.
4 5 6 1 In the fourth interval DU, the emission signal EM may have an activation level. For example, the activation level of the emission signal EM may be a logic low level. When the emission signal EM has the activation level, the fifth pixel switching element Sand the sixth pixel switching element Sare turned on. In addition, the first pixel switching element Sis also turned on by the data voltage VDATA.
5 1 6 The driving current may flow in the order of the fifth pixel switching element S, the first pixel switching element S, and the sixth pixel switching element Sto drive the light emitting element EE. The strength of the driving current may be determined by the level of the data voltage VDATA. The brightness of the light emitting element EE may be determined by the strength of the driving current.
7 FIG. 7 FIG. In, [N] refers to the signal of the current stage circuit, and in. Since the signal of the previous stage circuit or the next stage circuit is not applied to the pixel, [N] may be omitted.
The stage circuit according to example embodiments may be used to generate at least one of the write gate signal GW, the compensation gate signal GC, the data initialization gate signal GI, and the light emitting element initialization gate signal GB.
8 FIG. is a circuit diagram illustrating a stage circuit according to an example embodiment.
8 FIG. 11 1 2 3 1 21 Referring to, a stage circuitincludes a first transistor T, a second transistor T, a third transistor T, a first capacitor Cand a control circuit.
1 1 1 1 2 3 2 2 3 1 The first transistor Tis connected between an input terminal NI and a control terminal Q receiving an input signal SIN, and the first transistor Tincludes a gate electrode connected to a first clock terminal NCreceiving a first clock signal CLK. The second transistor Tis connected between a line supplying a gate high voltage VGH and an output terminal NO generating an output signal SOUT, and the second transistor includes a gate electrode connected to an inversion control terminal QB. The third transistor Tis connected between the output terminal NO and the second clock terminal NCreceiving the second clock signal CLK, and the third transistor Tincludes a gate electrode connected to the control terminal Q. The first capacitor Cis connected between the control terminal Q and the output terminal NO.
21 4 2 The control circuitmay include a fourth transistor Tand a second capacitor C.
4 4 2 1 The fourth transistor Tis connected between a line supplying the gate high voltage VGH and the inversion control terminal QB and the fourth transistor Tincludes a gate electrode connected to the control terminal Q. The second capacitor Cmay be connected between the first clock terminal NCand the inversion control terminal QB.
8 FIG. 1 2 3 4 In an example embodiment, as shown in, the first transistor T, the second transistor T, the third transistor T, and the fourth transistor Tmay be implemented as PMOS transistors.
9 FIG. 8 FIG. 10 10 FIGS.A throughE 8 FIG. 10 10 FIGS.A throughE is a diagram illustrating logic levels of signals and operations of transistors according to operation periods of the stage circuit of, andare diagrams illustrating operation of the stage circuit of. In, dashed arrows indicate paths for signals to be transferred, and dashed ellipses indicate transistors that are turned off.
2 FIGS. 8 9 10 1 1 2 1 3 4 2 Referring to.,, andA, in the first operation period P, the first clock signal CLKand the input signal SIN may be at a logic low level L and the second clock signal CLKmay be at a logic high level H. At this time, the first transistor Tthe third transistor T, and the fourth transistor Tmay be turned on, and the second transistor Tmay be turned off. As a result, the control voltage VQ may be at the logic low level L, and the inversion control voltage VQB may be at the logic high level H.
2 FIGS. 8 9 10 2 1 2 3 4 1 2 Referring to.,, andB, in the second operation period P, the first clock signal CLK, the second clock signal CLKand the input signal SIN may be at the logic high level H. At this time, the third transistor Tand the fourth transistor Tmay be turned on and the first transistor Tand the second transistor Tmay be turned off. As a result, the control voltage VQ may maintain the logic low level L and the inversion control voltage VQB may maintain the logic high level H.
2 FIGS. 8 9 10 3 2 1 3 4 1 2 1 Referring to.,, andC, in the third operation period P, the second clock signal CLKmay be at the logic low level L and the first clock signal CLKand the input signal SIN may be at the logic high level H. At this time, the third transistor Tand the fourth transistor Tmay remain turned on and the first transistor Tand the second transistor Tmay remain turned off. As a result, the control voltage VQ may be boosted to the boosting level L′ lower than the logic low level L by the coupling of the first capacitor C.
2 FIGS. 8 9 10 4 1 2 3 4 1 2 Referring to.,, andD, in the fourth operation period P, the first clock signal CLK, the second clock signal CLKand the input signal SIN may be at the logic high level H. At this time, the third transistor Tand the fourth transistor Tmay remain turned on and the first transistor Tand the second transistor Tmay remain turned off. As a result, the control voltage VQ may be restored to the logic low level L from the boosting level L′, and the inversion control voltage VQB may maintain the logic high level H.
2 FIGS. 8 9 10 5 1 2 1 2 3 4 Referring to.,, andE, in the fifth operation period P, the first clock signal CLKmay be at the logic low level L and the input signal SIN and the second clock signal CLKmay be at the logic high level H. At this time, the first transistor Tand the second transistor Tmay be turned on, and the third transistor Tand the fourth transistor Tmay be turned off. As a result, the control voltage VQ may be at the logic high level H, and the inversion control voltage VQB may be at the logic low level L.
11 FIG. is a circuit diagram illustrating a stage circuit according to an example embodiment.
11 FIG. 12 1 2 3 1 22 Referring to, a stage circuitincludes a first transistor T, a second transistor T, a third transistor T, a first capacitor Cand a control circuit.
1 1 1 1 2 3 2 2 3 1 The first transistor Tis connected between an input terminal NI and a control terminal Q receiving an input signal SIN, and the first transistor Tincludes a gate electrode connected to a first clock terminal NCreceiving a first clock signal CLK. The second transistor Tis connected between a line supplying a gate high voltage VGH and an output terminal NO generating an output signal SOUT, and the second transistor includes a gate electrode connected to an inversion control terminal QB. The third transistor Tis connected between the output terminal NO and the second clock terminal NCreceiving the second clock signal CLK, and the third transistor Tincludes a gate electrode connected to the control terminal Q. The first capacitor Cis connected between the control terminal Q and the output terminal NO.
22 4 2 The control circuitmay include a fourth transistor T, an enhancement transistor TN and a second capacitor C.
4 4 2 The fourth transistor Tis connected between the line supplying the gate high voltage VGH and the inversion control terminal QB, and the fourth transistor Tincludes a gate electrode connected to the control terminal Q. The enhancement transistor TN is connected between the inversion control terminal QB and a line supplying the gate low voltage VGL, and enhancement transistor TN includes a gate electrode connected to the control terminal Q. The second capacitor Cis connected between the line supplying the gate high voltage VGH and the inversion control terminal QB.
11 FIG. 1 2 3 4 In an example embodiment, as shown in, the first transistor T, the second transistor T, the third transistor T, and the fourth transistor Tmay be implemented with PMOS transistors, and the enhancement transistor TN may be implemented with an NMOS transistor.
12 FIG. 11 FIG. 2 FIG. 1 2 is a diagram illustrating logic levels of signals and operations of transistors according to operation periods of the stage circuit of. The input signal SIN, the first clock signal CLKand the second clock signal CLKare the same as described with reference to, and the redundant descriptions may be omitted.
2 11 12 FIGS.,, and 1 1 3 4 2 Referring to, in the first operation period P, the first transistor T, the third transistor Tand the fourth transistor Tmay be turned on, and the second transistor Tand the enhancement transistor TN may be turned off. As a result, the control voltage VQ may be at the logic low level L and the inversion control voltage VQB may be at the logic high level H.
2 3 4 1 2 In the second operation period P, the third transistor Tand the fourth transistor Tmay be turned on, and the first transistor T, the second transistor Tand the enhancement transistor TN may be turned off. As a result, the control voltage VQ may maintain the logic low level L, and the inversion control voltage VQB may maintain the logic high level H.
3 3 4 1 2 1 In the third operation period P, the third transistor Tand the fourth transistor Tmay remain turned on, and the first transistor T, the second transistor Tand the enhancement transistor TN may remain turned off. As a result, the control voltage VQ may be boosted to the boosting level L′ lower than the logic low level L by the coupling of the first capacitor C.
4 3 4 1 2 In the fourth operation period P, the third transistor Tand the fourth transistor Tmay remain turned on, and the first transistor T, the second transistor Tand the enhancement transistor TN may remain turned off. As a result, the control voltage VQ may be restored to the logic low level L from the boosting level L′, and the inversion control voltage VQB may maintain the logic high level H.
5 1 2 3 4 In the fifth operation period P, the first transistor T, the second transistor Tand the enhancement transistor TN may be turned on, and the third transistor Tand the fourth transistor Tmay be turned off. As a result, the control voltage VQ may be at the logic high level H, and the inversion control voltage VQB may be at the logic low level L.
13 FIG. is a circuit diagram illustrating a stage circuit according to an example embodiment.
13 FIG. 13 1 2 3 1 23 Referring to, a stage circuitincludes a first transistor T, a second transistor T, a third transistor T, a first capacitor Cand a control circuit.
1 1 1 1 2 3 2 2 3 1 The first transistor Tis connected between an input terminal NI and a control terminal Q receiving an input signal SIN, and the first transistor Tincludes a gate electrode connected to a first clock terminal NCreceiving a first clock signal CLK. The second transistor Tis connected between a line supplying a gate high voltage VGH and an output terminal NO generating an output signal SOUT, and the second transistor includes a gate electrode connected to an inversion control terminal QB. The third transistor Tis connected between the output terminal NO and the second clock terminal NCreceiving the second clock signal CLK, and the third transistor Tincludes a gate electrode connected to the control terminal Q. The first capacitor Cis connected between the control terminal Q and the output terminal NO.
23 4 2 The control circuitmay include a fourth transistor T, an enhancement transistor TN, and a second capacitor C.
4 4 2 2 The fourth transistor Tis connected between the line supplying the gate high voltage VGH and the inversion control terminal QB and the fourth transistor Tincludes a gate electrode connected to the second clock terminal NC. The enhancement transistor TN is connected between the inversion control terminal QB and a line supplying the gate low voltage VGL, and the enhancement transistor TN includes a gate electrode connected to the control terminal Q. The second capacitor Cis connected between the line supplying the gate high voltage VGH and the inversion control terminal QB.
13 FIG. 1 2 3 4 In an example embodiment, as shown in, the first transistor T, the second transistor T, the third transistor Tand the fourth transistor Tmay be implemented with PMOS transistors, and the enhancement transistor TN may be implemented with an NMOS transistor.
14 FIG. 13 FIG. 2 FIG. 1 2 is a diagram illustrating logic levels of signals and operations of transistors according to operation periods of the stage circuit of. The input signal SIN, the first clock signal CLKand the second clock signal CLKare the same as described with reference to, and the redundant descriptions may be omitted.
2 13 14 FIGS.,, and 1 1 2 3 4 Referring to, in the first operation period P, the first transistor T, the second transistor T, and the third transistor Tmay be turned on, and the fourth transistor Tand the enhancement transistor TN may be turned off. As a result, the control voltage VQ may be at the logic low level L and the inversion control voltage VQB may be at the logic high level H.
2 2 3 1 4 In the second operation period P, the second transistor Tand the third transistor Tmay be turned on, and the first transistor T, the fourth transistor Tand the enhancement transistor TN may be turned off. As a result, the control voltage VQ may maintain the logic low level L, and the inversion control voltage VQB may maintain the logic high level H.
3 3 4 1 2 1 In the third operation period P, the third transistor Tand the fourth transistor Tmay be turned on, and the first transistor T, the second transistor T, and the enhancement transistor TN may be turned off. As a result, the control voltage VQ may be boosted to the boosting level L′ lower than the logic low level L by the coupling of the first capacitor C.
4 2 3 1 4 In the fourth operation period P, the second transistor Tand the third transistor Tmay be turned on, and the first transistor T, the fourth transistor Tand the enhancement transistor TN may be turned off. As a result, the control voltage VQ may be restored to the logic low level L from the boosting level L′, and the inversion control voltage VQB may remain at the logic high level H.
5 1 2 3 4 In the fifth operation period P, the first transistor T, the second transistor Tand the enhancement transistor TN may be turned on, and the third transistor Tand the fourth transistor Tmay be turned off. As a result, the control voltage VQ may be at the logic high level H, and the inversion control voltage VQB may be at the logic low level L.
15 FIG. is a circuit diagram illustrating a stage circuit according to an example embodiment.
15 FIG. 14 1 2 3 1 24 Referring to, a stage circuitincludes a first transistor T, a second transistor T, a third transistor T, a first capacitor C, and a control circuit.
1 1 1 1 2 3 2 2 3 1 The first transistor Tis connected between an input terminal NI and a control terminal Q receiving an input signal SIN, and the first transistor Tincludes a gate electrode connected to a first clock terminal NCreceiving a first clock signal CLK. The second transistor Tis connected between a line supplying a gate high voltage VGH and an output terminal NO generating an output signal SOUT, and the second transistor includes a gate electrode connected to an inversion control terminal QB. The third transistor Tis connected between the output terminal NO and the second clock terminal NCreceiving the second clock signal CLK, and the third transistor Tincludes a gate electrode connected to the control terminal Q. The first capacitor Cis connected between the control terminal Q and the output terminal NO.
24 4 The control circuitmay include a fourth transistor Tand an enhancement transistor TN.
4 1 4 The fourth transistor Tis connected between the first clock terminal NCand the inversion control terminal QB, and the fourth transistor Tincludes a gate electrode connected to the control terminal Q. The enhancement transistor TN is connected between the inversion control terminal QB and a line supplying the gate low voltage VGL, and the enhancement transistor TN includes a gate electrode connected to the control terminal Q.
15 FIG. 1 2 3 4 In an example embodiment, as shown in, the first transistor T, the second transistor T, the third transistor Tand the fourth transistor Tmay be implemented with PMOS transistors, and the enhancement transistor TN may be implemented with an NMOS transistor.
16 FIG. 15 FIG. 2 FIG. 1 2 is a diagram illustrating logic levels of signals and operations of transistors according to operation periods of the stage circuit of. The input signal SIN, the first clock signal CLKand the second clock signal CLKare the same as described with reference to, and the redundant descriptions may be omitted.
2 15 16 FIGS.,, and 1 1 2 3 4 Referring to, in the first operation period P, the first transistor T, the second transistor T, the third transistor Tand the fourth transistor Tmay be turned on, and the enhancement transistor TN may be turned off. As a result, the control voltage VQ may be at the logic low level L and the inversion control voltage VQB may be at the logic high level H.
2 3 4 1 2 In the second operation period P, the third transistor Tand the fourth transistor Tmay be turned on, and the first transistor T, the second transistor Tand the enhancement transistor TN may be turned off. As a result, the control voltage VQ may maintain the logic low level L and the inversion control voltage VQB may maintain the logic high level H.
3 3 4 1 2 1 In the third operation period P, the third transistor Tand the fourth transistor Tmay remain turned on, and the first transistor T, the second transistor Tand the enhancement transistor TN may remain turned off. As a result, the control voltage VQ may be boosted to the boosting level L′ lower than the logic low level L by the coupling of the first capacitor C.
4 3 4 1 2 In the fourth operation period P, the third transistor Tand the fourth transistor Tmay remain turned on, and the first transistor T, the second transistor T, and the enhancement transistor TN may remain turned off. As a result, the control voltage VQ may be restored to the logic low level L from the boosting level L′, and the inversion control voltage VQB may maintain the logic high level H.
5 1 2 3 4 In the fifth operation period P, the first transistor T, the second transistor Tand the enhancement transistor TN may be turned on, and the third transistor Tand the fourth transistor Tmay be turned off. As a result, the control voltage VQ may be at the logic high level H and the inversion control voltage VQB may be at the logic low level L.
17 18 19 20 FIGS.,,and are circuit diagrams illustrating stage circuits according to example embodiments.
5 15 11 16 12 17 13 18 14 17 FIG. 8 FIG. 18 FIG. 11 FIG. 19 FIG. 13 FIG. 20 FIG. 15 FIG. Except for further inclusion of a load reduction transistor T, a stage circuitofis substantially the same as the stage circuitof, a stage circuitofis substantially the same as the stage circuitof, a stage circuitofis substantially the same as the stage circuitof, and a stage circuitofis substantially the same as the stage circuitof, and the redundant description may be omitted.
5 5 1 The load reduction transistor Tmay be connected between an intermediate terminal NA and the control terminal Q. In other words, the load reduction transistor Tmay be connected in series with the first transistor Tbetween the input terminal NI and the control terminal Q.
5 5 The gate low voltage VGL may be applied to the gate electrode of the load reduction transistor T. Thus, the load reduction transistor Tmay always be turned on during operation of the stage circuit.
3 1 1 5 1 1 As described above, in the third operation interval P, the control voltage VQ of the control terminal Q drops to a further lower level. In this case, the source-drain voltage of the first transistor Tincreases further, which may promote degradation of the first transistor Tor cause breakdown. By adding the load reduction transistor T, the load on the first transistor Tmay be distributed to reduce the degradation of the first transistor Tand prevent breakdown.
21 FIG. 22 FIG. 21 is a block diagram illustrating an electronic device according to example embodiments, andis a diagram illustrating an example of the electronic device of FIG.implemented as a smartphone.
1 22 FIGS.through 3 FIG. 1000 1010 1020 1030 1040 1050 1060 1060 1000 Referring to, an electronic devicemay include a processor, a memory device, a storage device, an input/output device, a power supply, and a display device. The display devicemay correspond to the display device of. In addition, the electronic devicemay further include multiple ports for communicating with a video card, sound card, memory card, USB device, or the like, or for communicating with other systems.
1000 1000 1000 22 FIG. According to example embodiments, the electronic devicemay be implemented as a smartphone, as shown in, but the electronic deviceis not limited thereto. For example, the electronic devicemay be implemented as a cell phone, videophone, smart pad, smartwatch, tablet PC, in-vehicle navigation, computer monitor, a laptop computer, a head-mounted display device, or the like.
1010 1010 1010 1010 The processormay perform certain calculations or tasks. The processormay be a microprocessor, a central processing unit, an application processor, or the like. The processormay be connected to other components via an address bus, a control bus, a data bus, and the like. Depending on the example embodiment, the processormay also be connected to an expansion bus, such as a Peripheral Component Interconnect (“PCI”) bus.
1010 200 3 FIG. The processormay output the input image data IMG and the input control signal CONT to the drive controllerof.
1020 1000 The memory devicemay store data necessary for operation of the electronic device. Nano Floating Gate Memory (“NFGM”) devices, Polymer Random Access Memory (“PoRAM”) devices, Magnetic Random Access Memory (“MRAM”) devices, Ferroelectric Random Access Memory (“FRAM”) devices, and/or non-volatile memory devices such as Dynamic Random Access Memory (“DRAM”) devices, Static Random Access Memory (“SRAM”) devices, Mobile DRAM devices, and the like.
1030 1040 1060 1040 1050 1000 1060 The storage devicemay include a solid state drive (“SSD”), a hard disk drive (“HDD”), a CD-ROM, or the like. Input/output devicesmay include input means such as a keyboard, keypad, touchpad, touchscreen, mouse, etc. and output means such as speakers, printers, etc. According to example embodiments, the display devicemay be included in the I/O device. The power supplymay provide power for operation of the electronic device. The display devicemay be connected to other components via the above buses or other communication links.
1060 The display devicemay include stage circuit according to example embodiments as described above.
As described above, the stage circuit according to example embodiments may be implemented with fewer transistors, thereby reducing the size of the gate driver including the stage circuits and reducing the dead space in the display panel without sacrificing performance of the gate driver. In addition, the stage circuit according to example embodiments may utilize boosting via capacitors to improve the waveform of the output signal, thereby enhancing the performance of the display device including the stage circuits. Further, the stage circuit according to example embodiments may remove unnecessary operation of the display device and reduce wiring routing in the display device by using fewer transistors and capacitors, thereby improving the design margin of the display device.
Example embodiments may be applied to a display device and any electronic devices and systems including a display device. For example, the example embodiments may be applied to systems such as a mobile phone, a smart phone, a personal digital assistant (“PDA”), a portable multimedia player (“PMP”), a digital camera, a camcorder, a personal computer (“PC”), a server computer, a workstation, a laptop computer, a digital TV, a set-top box, a portable game console, a navigation system, a wearable device, an internet of things (“IoT”) device, an internet of everything (“IoE”) device, an e-book, a virtual reality (“VR”) device, an augmented reality (“AR”) device, a server system, an automotive driving system, etc.
The foregoing is illustrative of example embodiments and is not to be construed as limiting thereof. Although a few example embodiments have been described, those skilled in the art will readily appreciate that many modifications are possible in the example embodiments without materially departing from the example embodiments.
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December 2, 2024
August 18, 2026
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